Update apache.conf

[hgomez]

Some Apache distribution came with following error handling

Alias /error/ "/usr/share/apache2/error/"

<IfModule mod_negotiation.c>
<IfModule mod_include.c>
    <Directory "/usr/share/apache2/error">
        AllowOverride None
        Options IncludesNoExec
        AddOutputFilter Includes html
        AddHandler type-map var
        Require all granted
        LanguagePriority en cs de es fr it ja ko nl pl pt-br ro sv tr
        ForceLanguagePriority Prefer Fallback
    </Directory>

    ErrorDocument 400 /error/HTTP_BAD_REQUEST.html.var
    ErrorDocument 401 /error/HTTP_UNAUTHORIZED.html.var
    ErrorDocument 403 /error/HTTP_FORBIDDEN.html.var
    ErrorDocument 404 /error/HTTP_NOT_FOUND.html.var
    ErrorDocument 405 /error/HTTP_METHOD_NOT_ALLOWED.html.var
    ErrorDocument 408 /error/HTTP_REQUEST_TIME_OUT.html.var
    ErrorDocument 410 /error/HTTP_GONE.html.var
    ErrorDocument 411 /error/HTTP_LENGTH_REQUIRED.html.var
    ErrorDocument 412 /error/HTTP_PRECONDITION_FAILED.html.var
    ErrorDocument 413 /error/HTTP_REQUEST_ENTITY_TOO_LARGE.html.var
    ErrorDocument 414 /error/HTTP_REQUEST_URI_TOO_LARGE.html.var
    ErrorDocument 415 /error/HTTP_UNSUPPORTED_MEDIA_TYPE.html.var
    ErrorDocument 500 /error/HTTP_INTERNAL_SERVER_ERROR.html.var
    ErrorDocument 501 /error/HTTP_NOT_IMPLEMENTED.html.var
    ErrorDocument 502 /error/HTTP_BAD_GATEWAY.html.var
    ErrorDocument 503 /error/HTTP_SERVICE_UNAVAILABLE.html.var
    ErrorDocument 506 /error/HTTP_VARIANT_ALSO_VARIES.html.var
</IfModule>
</IfModule>

In this case, you shouldn't proxy /error/ to docker-registry

[hgomez]

Also updated configuration to allow /_ping URI too As found in nginx configuration

[dmp42]

Thanks for this!